Unitary optical assembly



April 9, 1940. M. E. COLLINS UNITARY OPTICAL ASSEMBLY 2 Shets-Sheet 1OriginalFiled July 30, 1937 M'lford if Col/ins A TTORNE Y APl'il9,1940-M. E. COLLINS 2,196,583

UNH'ARY OPTICAL ASSEMBLY Original Filed July 30, 1937 2 She ets-Sheet 2IIIIIIIIIIIIIIIIHI Milford 601/1725 Arr-021w: y-

Patented Apr. 9, 1940 UNITED STATES.

r 2,196,583- nm'ranr omen. ASSEMBLY more 1;. Collins, Hollywood,

-Badlo Corporation of America,

of Delaware mans application July 156,506. Divided and this application193a, set-nine. 210,661

8 Claims. "(cuss-a This invention relates to motion pictureprintingapparatus and particularly to the optical portionof such printerswherein an image on a negative film is projected to a positive film, the

image on the positivebeing either of the same dimensions or of differentdimensions from that on the negative.

The printing of the sound track on a motion picture film, particularlywhen the dimensions 10 thereof are changed during the printing process,

requires accurate positioning of all the vital elementssuch asthelight'source, films, reflectors and lenses, while the printer itselfrequires a rugged construction for commercal purposes. In

the manufacture of motion picture film printing apparatus, therefore, itis desirable that all possible fixed adjustments between cooperatingelements be made at the factory or assembling plant where the necessaryequipment and engineering skill are present. Particularly is this trueof the optical portion of the printers involving theli'ght source andlenses which project the'light beam to the negative and then from thenegative to the positive; In an 'anamorphosing system wherein a soundtrack is being piinted to smaller;

dimensions or to dimensions different from those of the originalsoundtrack, adjustment of these lenses is particularly critical. Some ofthese adjustments are the orientation of the azimuths of thenon-spherical lenses and the focusing for position and size of the lightsource upon the surface of the negative film, and of the ifiiilgiulatedbeam upon the surface of the positive 85 This application is a divisionof my copending application, Serial No. 156,506, filed July 30, 1937,disclosing the general. arrangement of optical units, .film drive andmeans. for adjusting the lateral position of the film with respect tothe 40 light beam. The present invention is directed to the opticalimits themselves which are assemblies embodying novel constructions toadjusting-the various l'enses'and other optica elements employedtherein. A particular feature of the invention described in theabove-mentioned copending application is the unitary optical assemblyintermediate the negative and positive films. This unitjafter theindividual elements thereof have beenadjusted and sealed, is doweledto'the supporting'plate in a fixed relationship with respect to thefilms, the surfaces of which are fixed by rollers over which the filmspass. The method of and means for adjusting the azimuth and focus of'thevarious lenses and the construction of the optical as- OaliL, seam to acorporation :0, 1921, Serial 'No. 5

May 28,

semblies is involved in the present invention. The adjustments may bemade quickly and accurateiy within a rugged imitary assembly suitablefor mountingmn the. printer mounting plate.

An object of the invention, therefore isto 6 facilitate the adjustmentof the various lenses of an optical assembly during construction of a.

film printer.

Another object of the invention is to. provide. within a complex unitaryoptical assembly means for adjustingtheindividual elements thereof.

A further object of the inventioh. is to unitize a plurality of opticalelements whereby the unit may be bodily translated between an object andthe image thereof. 7 Although the novel features which are believed tobe characteristic of this invention will be pointed out withparticularity in-the claims appending herewith, the invention itself,its objects and advantages, the manner of its organization and the modeof its operation will be better understood by referring to the followingdescription read in conjunction with the accompanying drawings formingapart thereof, in which:

Figure 1 is a sectional plan view of a printer in which the opticalassembly embodying the features of the invention isshown in'cr'oss-sec-".l Figure 2 is a schematic plan view of the optical arrangement of Fig.1:

Figure 3 is a cross-sectional view of the lamphouse and associateoptical elements taken along the line 3-3 of'Fig. 1;

Figure 4 is a'partial cross-sectional view taken along the line. 4-4 ofFig. 1; and

Figure 5 is across-sectional view taken along theline550fFlg;4.Referring now. to the drawings in which the same numerals identify likeelements, and particularly to Fig. 1, a frame plate 5 serves as a mountcommon to the optical assemblies, rollers, sprockets and other printerfilm advancing ele-' ments. A negative film 6 'is passed over a roller 1guided by an edge-guide roller 8 and a. wrapping roller 9. A positivefilm ii is passed over a 45 roller l2 edge-guided by a roller l3, thedetails .of the negative and positive film paths being, shown in detailin the above-mentioned. co-

pending' application. v

Light from a' source suc as a lamp l5 housed in a casing i6 is gatheredby an optical assembly l8 including lenses l9, 9. rhomboid reflector 20,and an objective lens 2|. (See Figs. 2 and 3.) These optical elementsare mounted'withina housing 2:, the rhomboid reflector 2i being 56mounted in a cylindrical sleeve adjustable within a hollow portion ofthe housing 23 to alignthe light beam with respect to lenses l9 and 2|.The housing 23 as a unit is adjustable along the optical axis of lensesl9 within a boss 24 of the lamp casing l6, and when adjusted is maintained in fixed position by a set screw 26. The

adjustment of the assembly l8 within the casing |6 adjusts the focusingof the light upon the negative film 6.

The lamp I5 is held in position in its support 21 by a clamping collar28 about the lamp base under control of a finger screw 29. The support27 is adjustable lat rally upon pins 32 and 33 and locked in posit iothereon by a nut 34. After adjustments of the lamp and of the assembly I8 have been made /the entire housing l6 may be adjusted as a ole uponplate 5 and accurately positioned the eon by means of dowel pins 35 and36, screws 3| being the fastening means.

Referring ,now to the optical assembly 31 which may vary lie dimensionsof the beam emerging from the negative 6 for projection upon thepositive objective lens 39, a cylindrical lens 46, a reversing lens 4|,a cylindrical lens 42, and an obj, tive lens 43 are included within thebarrel or tu'be portion 30 of a mounting fixture having a base 3| (seeFig. 5). The lenses 46, 4| and 42 are for the purpose of anamorphosingand reversing the image, reversal of the image being necessary sinceboth the negative and positive films travel in the same direction withtheir emulsion sides toward one'another.

The objective lens 39 is mounted in a holder 44 slidable longitudinallywithin the barrel 36 by action of a knurled ring 46 threaded on aportion 45 thereof. The ring. 46 extends beyond the circumference-ofbarrel 30 for manual adjustment of the objective lens 39 along itsoptical axis (see Fig. 4). The holder 44 for lens 39 is held in anyadjusted position by means of a set screw 41 threaded therein, the screw41 passing through a slot 48 of the tube 30. The head of the screw 41 iscarried by a block slidable on the tube 30. At the other end of the tube36, the objective lens 43 is similarly adjustable by being mounted in aholder 49 having a threaded portion 50, the latter being threaded withina knurled ring 5|. The holder 49 in which lens 43 is mounted is lockedin adjusted position by means of a set screw 52 slidable in a block 54in a slot 53 of the tube 30 in the same manner as the arrangement at theother end of the tube. When the lenses 39 and 43 have been adjusted thescrews 41 and 52 may be sealed.

Referring now to the mounting of the three cylindrical lenses 40, 4| and42, these lenses are spaced with respect to one another by means ofcylinders 51, 58 and 59 within a broached cylinder or lens barrel 56. Acompression spring 66 interposed between cylinders 51 and 56 maintainsthe lenses in a fixed longitudinal position, the spring reacting againsta stop H and an exteriorly threaded nut 59 threaded in the other end ofcylinder 56. This broached cylindrical unit, including lenses 40, 4| and42, is adjustable longitudinally as a unit by means of a screw 6|threaded therein and slidable within a cut-out portion 62 of the barrel36 (see Fig. 4). The screw 6| also functions as a set screw to aid inthe assembly of the cylindrical lenses by holding the spacing cylinder51 in place while lens 46 and nut 59' are being positioned. A plate 63held in position by screws 64 covers the opening 62. R0- tationaladjustment or the cylinder 56 within tube accurate adjustment of thefive lenses with respect to one another during assembly of the unit,after which no further attention need be given to it unless damaged. Forinstance, after the lenses have been adjusted with respect to eachother, the adjusting means may be sealed. During these adjustments thebase 3| is held to the plate 5 by the screws 10, the holes thereof beingoversize to provide for slight movement of base 3|. When the position ofthe assembly has been determined, it is fixedly positioned on plate 5 bydowel pins I I, within cooperating holes in base 3| and plate 5.. Theunit is then removable as a whole for repair and adjustment and may bereplaced upon the'dowels in its exact former position.

In Fig. 2, an eyepiece 61 is shown positioned at right angles to theoptical axis of the optical system and directed at a light transmittingreflector 66 positioned at an angle of 45 to the optical axis of thesystem. This optical unit is used in making adjustments at the factoryand particularly for checking the focusing-of the light beam upon thesurface of positive film A cap 69 is placed over the opening in the.tube after removal of the eyepiece and reflector.

.It is to be noted that since lenses 46, 4| and 42 are only for thepurpose of varying dimensions and image reversal, their positions arefixed with respect to one another along their common optical axis by.spacers 51, 56 and 59. However, they are adjustable as a unit within thetube 30, and when the unit is adjusted, it may be locked by set screw 6|which may be sealed. Plate 63 then covers the seal. Similarly, theadjustment of the objective lenses 39 and 43 by the knurled washers 46and 5| may be locked in' position by 'set screws 41 and 52,respectively, after which these screws may be sealed to prevent casualadjus cut. The azimuth or rotational adjustment of the unit accomplishedby screws and 66 may be fixed by sealing screws 65 and 66 in theirfinal, adjusted position. At the factory, where skilled engineers arefamiliar with the optical elements of assembly 31, these adjustments maybe accurately and quickly made with respect to the film surfaces onrollers I. and I2.

Thus, both optical assemblies comprising the unit for impressing thelight upon the negative film and the unit for transferring the emergentlight to the positive film are both unitary to the extent that each unitcan'be handled and operated as a single element, although composed of aplurality of cooperating, pre-adjusted elements. These particularoptical units have contributed largely to the commercial success ofsound film printing wherein sharp and clear images on the positive havebeen uniformly obtained under commercial conditions. I

I claim as my invention:

1. A unitary optical assembly comprising a plurality of different typesof optical elements, a cylindrical housing for said elements, lenses ofa similar type at the ends of said cylindrical housing. means foradjusting said similar optical elements longitudinally of saidcylindrical housing, said means comprising cylindrical threaded ringsconcentric with and extending beyond the circumference of saidcylindrical housing, a cylindrical member within said first cylindricalhousing intermediate said similar optical elements and adapted forlongitudinal adjustment between and along the optical axis of saidlenses of similar type and for rotational movement, a plurality ofcooperating optical elements positioned within said cylindrical membersaid member maintaining the orientation of each of said optical elementsfixed with respect to one another, a plurality of spacing members withinsaid second cylindrical member for maintaining the focus of each'of saidopticalelements fixed with respect to one another,-and means foradjusting the azimuth and focus of said cooperating optical elements asa unit with respect to said lenses of similar type.

2. An optical assembly comprising a cylindricalhousing adapted formounting on film apparatus;-a lens mounted within one end of saidcylindricahmember, a second lens mounted at the other end of saidcylindrical member, respective supports for said lenses slidable withinsaid housing and having threaded portions thereon, interiorly threadedcylindrical rings mounted on the threaded portions of said supports andextending outside of said cylindrical housing for longitudinallyadjusting said lenses along their optical axes, means for lockingsaidsupports in any adjusted position, a cylinder interposed be- I tweensaid lenses within said cylindrical housing, a plurality of lenseswithin said cylinder, said cylinder being broached parallel to thecommon optical axis of said plurality of lenses to maintain theorientation of each of said plurality of lenses fixed with respect toone another a plurality of spacing members within said broached cylinderand coacting therewith for longitudinally spacing said plurality oflenses and maintaining the focus of each of saidplurality of lensesfixed with respect 'to one another, means for rotating andlongitudinally adjusting said cylinder within said cylindrical housingfor relating said plurality of lenses as a unit with saidfirst-mentioned lenses, and means for fixing said cylinder in anyadjusted position.

3. An optical assembly in accordance with claim 2 in which means areprovided for sealing all of said adjusting means.

4. An optical unit adapted for unitary adjustment between a fixed objectand a surface upon which the image of said object is projected,comprising a mounting having a cylindrical housing portion,said'mounting being adapted for attachment to film apparatus, a lensmounted adjacent each end of said cylindrical housing, respectiveholders for said lenses, said holders being-adapted for longitudinalmovement within said housing along the optical axes of said lenses andhaving respective threaded portions thereon, interiorly threaded ringsmounted on respective threaded portions of said holders, said ringsprojecting through slots in said housing, rotation of said rings movingsaid lenses along their optical axes, means connected to said holdersand extending exter ally of said housing for locking said holders irespective adjusted positions, a lens barrel within said housing andintermediate said holders, said lens barrel being broached longimentbetween a fixed object and a surface upon which the image of said objectis projected comprising a mounting having a cylindrical housing portion,said mounting being adapted for attachment to film apparatus, a lensbarrel within said cylindrical housing, said barrel being broachedlongitudinally and substantially parallel to the axis thereof aplurality of cooperating lenses mounted within said lens barrel, aplurality of coaxial tubes carried by said lens barrel, said broachedlens barrel and coaxial tubes coacting to maintain the orientation ofeach of said cooperating lenses fixed with respect to each other and forfixedly spacing said elements longitudinally along said lens barrel,means 'for rotating and longitudinally adjusting said lens barrel andsaid cooperating. lenses as a unit within said housing, a lens at eachend portion of said cylindrical housing, and means extending externallyof said housing for longitudinally adjusting each of said lenses withrespect to the cooperating lenses within said lens barrel.

6. A unitary optical assembly in accordance with claim in which meansare provided for locking said lens barrel and said lenses at the ends ofsaid housing in any adjusted position, said means permitting sealing ofsaid locking means.

7. A unitary optical unit comprising a housing, a lamp, means foradjustably supporting said lamp on and withinsaid housing, a cylindricalboss integral with said housing, a cylindrical member within said bossand adapted for adjustment along the coincident axis of said member andsaid boss, a plurality of lenses within said cylindrical member andhaving an optical axis coincident with the axis of said member and saidboss, said cylindrical member having a transverse cylindrical portion,and a second cylindrical member within said transverse cylindricalportion and having a reflecting optical element therein for shifting theaxis of said light beam; passing through said lenses, all of saidabovementioned elements being adjustable as a unit withv respect to animage surface.

8. An optical assembly comprising a casing, a lens barrel in said casingand interiorly broached with grooves longitudinally thereof andsubstantially parallel to the axis of said lens barrel, a plurality ofcoaxial tubes within said lens barrel, a plurality of lensesintermediate said tubes, means supporting said lenses and coacting withsaid tubes and the grooves in said lens barrel for maintaining theorientation of each of said lenses fixed with respectto one another, asecond plurality of lenses in said casing, and means for adjusting saidfirst plurality of lenses as a unit both as to focus and orientationwith respect to said second plurality of lenses.

g MILFORD E. COLLINS.

